I tested this script on 5 new tutorial island accounts and these were my results,
Seems like there may be a bug with witch's potion on the final step the bot gets stuck drinking from the cauldron.
I found a few other errors that caught the bot up
Step 81: Varrock palace door
Step 114: Ernest the chicken maze (I tested this quest on its own and the bot was able to complete the maze just fine but for some reason in the speedrun it gets stuck at various points)
Step 184: The bot attempts to exit the black knights fortress from the wrong door leading to it getting stuck.